Chapter 1 Introduction to Cryptography
Total Page:16
File Type:pdf, Size:1020Kb
Load more
Recommended publications
-
A Quantitative Study of Advanced Encryption Standard Performance
United States Military Academy USMA Digital Commons West Point ETD 12-2018 A Quantitative Study of Advanced Encryption Standard Performance as it Relates to Cryptographic Attack Feasibility Daniel Hawthorne United States Military Academy, [email protected] Follow this and additional works at: https://digitalcommons.usmalibrary.org/faculty_etd Part of the Information Security Commons Recommended Citation Hawthorne, Daniel, "A Quantitative Study of Advanced Encryption Standard Performance as it Relates to Cryptographic Attack Feasibility" (2018). West Point ETD. 9. https://digitalcommons.usmalibrary.org/faculty_etd/9 This Doctoral Dissertation is brought to you for free and open access by USMA Digital Commons. It has been accepted for inclusion in West Point ETD by an authorized administrator of USMA Digital Commons. For more information, please contact [email protected]. A QUANTITATIVE STUDY OF ADVANCED ENCRYPTION STANDARD PERFORMANCE AS IT RELATES TO CRYPTOGRAPHIC ATTACK FEASIBILITY A Dissertation Presented in Partial Fulfillment of the Requirements for the Degree of Doctor of Computer Science By Daniel Stephen Hawthorne Colorado Technical University December, 2018 Committee Dr. Richard Livingood, Ph.D., Chair Dr. Kelly Hughes, DCS, Committee Member Dr. James O. Webb, Ph.D., Committee Member December 17, 2018 © Daniel Stephen Hawthorne, 2018 1 Abstract The advanced encryption standard (AES) is the premier symmetric key cryptosystem in use today. Given its prevalence, the security provided by AES is of utmost importance. Technology is advancing at an incredible rate, in both capability and popularity, much faster than its rate of advancement in the late 1990s when AES was selected as the replacement standard for DES. Although the literature surrounding AES is robust, most studies fall into either theoretical or practical yet infeasible. -
Vigenère Cipher Cryptanalysis
Spring 2015 Chris Christensen MAT/CSC 483 Cryptanalysis of the Vigenère Cipher: Kasiski Test The keyword of a Vigenère cipher describes the rotation among the Caesar cipher alphabets that are used. That rotation leads to patterns that can be exploited by a cryptanalyst. If we know the length of the keyword, we can often determine the keyword and, hence, decrypt all messages encrypted with that keyword. Here is a ciphertext message that has been encrypted with a Vigenère cipher. nifon aicum niswt luvet vxshk nissx wsstb husle chsnv ytsro cdsoy nisgx lnona chvch gnonw yndlh sfrnh npblr yowgf unoca cossu ouoll iuvef issoe xgosa cpbew uormh lftaf cmwak bbbdv cqvek muvil qbgnh ntiri ljgig atwnv yuvev iorim cpbsb hxviv buvet vxshk uorim mjbdb pjrut fbueg ntgof yuwmx miodm ipdek uuswx lfjek sewfy yssnm zscmm bpgeb huvez ysaag usaew mffvb wfgim qpilw bbjeu yfbef vbfrt mtwnz uorig wpbvx hjsnm zpfag uhsnm npglb jbqrh mttrh huwek mpfak ljjen hbbnh ooqew vzdak udvum yucbx yoquf vffew vzonx hjumt lfgef vmwnz uxsiz bumag xbbtb kvotx xumpx qswtx l Assume that, somehow, we have discovered that the keyword has length five (which is conveniently the same as the size of the blocks). Then the first letter of each block is encrypted with the same row of the Vigenère square – they are encrypted with the same Caesar cipher. Similarly, the second letter of each block is encrypted with the same row – the same Caesar cipher. The third letters with the same Caesar cipher. The fourth letters with the same Caesar cipher. And, the fifth letters with the same Caesar cipher. -
On the NIST Lightweight Cryptography Standardization
On the NIST Lightweight Cryptography Standardization Meltem S¨onmez Turan NIST Lightweight Cryptography Team ECC 2019: 23rd Workshop on Elliptic Curve Cryptography December 2, 2019 Outline • NIST's Cryptography Standards • Overview - Lightweight Cryptography • NIST Lightweight Cryptography Standardization Process • Announcements 1 NIST's Cryptography Standards National Institute of Standards and Technology • Non-regulatory federal agency within U.S. Department of Commerce. • Founded in 1901, known as the National Bureau of Standards (NBS) prior to 1988. • Headquarters in Gaithersburg, Maryland, and laboratories in Boulder, Colorado. • Employs around 6,000 employees and associates. NIST's Mission to promote U.S. innovation and industrial competitiveness by advancing measurement science, standards, and technology in ways that enhance economic security and improve our quality of life. 2 NIST Organization Chart Laboratory Programs Computer Security Division • Center for Nanoscale Science and • Cryptographic Technology Technology • Secure Systems and Applications • Communications Technology Lab. • Security Outreach and Integration • Engineering Lab. • Security Components and Mechanisms • Information Technology Lab. • Security Test, Validation and • Material Measurement Lab. Measurements • NIST Center for Neutron Research • Physical Measurement Lab. Information Technology Lab. • Advanced Network Technologies • Applied and Computational Mathematics • Applied Cybersecurity • Computer Security • Information Access • Software and Systems • Statistical -
BALG: Bypassing Application Layer Gateways Using Multi-Staged Encrypted Shellcodes
Sebastian Roschke, Feng Cheng, Christoph Meinel: "BALG: Bypassing Application Layer Gateways Using Multi-Staged Encrypted Shellcodes" in Proceedings of the 12th IFIP/IEEE International Symposium on Integrated Network Management (IM 2011), IEEE Press, Dublin, Ireland, pp. 399-406, 5, 2011. ISBN: 978-1-4244-9219-0. BALG: Bypassing Application Layer Gateways Using Multi-Staged Encrypted Shellcodes Sebastian Roschke Feng Cheng Christoph Meinel Hasso Plattner Institute (HPI) Hasso Plattner Institute (HPI) Hasso Plattner Institute (HPI) University of Potsdam University of Potsdam University of Potsdam 14482, Potsdam, Germany 14482, Potsdam, Germany 14482, Potsdam, Germany Email: [email protected] Email: [email protected] Email: [email protected] Abstract—Modern attacks are using sophisticated and inno- easily penetrated by simple tunneling. IDS needs to handle vative techniques. The utilization of cryptography, self-modified efficient evasion techniques. ALGs provide more restrictions code, and integrated attack frameworks provide more possibili- for network access by combining filtering on the application ties to circumvent most existing perimeter security approaches, such as firewalls and IDS. Even Application Layer Gateways layer and IDS techniques, such as deep packet inspection. (ALG) which enforce the most restrictive network access can be Most of ALG implementations provide filtering due to ap- exploited by using advanced attack techniques. In this paper, plication layer protocol compliance and even allow to block we propose a new attack for circumventing ALGs. By using certain commands within a specific protocol. Although ALGs polymorphic and encrypted shellcode, multiple shellcode stages, enforce a very restrictive access policy, it is still possible to protocol compliant and encrypted shell tunneling, and reverse channel discovery techniques, we are able to effectively bypass circumvent such devices by using modern attack techniques. -
TS 102 176-1 V2.1.1 (2011-07) Technical Specification
ETSI TS 102 176-1 V2.1.1 (2011-07) Technical Specification Electronic Signatures and Infrastructures (ESI); Algorithms and Parameters for Secure Electronic Signatures; Part 1: Hash functions and asymmetric algorithms 2 ETSI TS 102 176-1 V2.1.1 (2011-07) Reference RTS/ESI-000080-1 Keywords e-commerce, electronic signature, security ETSI 650 Route des Lucioles F-06921 Sophia Antipolis Cedex - FRANCE Tel.: +33 4 92 94 42 00 Fax: +33 4 93 65 47 16 Siret N° 348 623 562 00017 - NAF 742 C Association à but non lucratif enregistrée à la Sous-Préfecture de Grasse (06) N° 7803/88 Important notice Individual copies of the present document can be downloaded from: http://www.etsi.org The present document may be made available in more than one electronic version or in print. In any case of existing or perceived difference in contents between such versions, the reference version is the Portable Document Format (PDF). In case of dispute, the reference shall be the printing on ETSI printers of the PDF version kept on a specific network drive within ETSI Secretariat. Users of the present document should be aware that the document may be subject to revision or change of status. Information on the current status of this and other ETSI documents is available at http://portal.etsi.org/tb/status/status.asp If you find errors in the present document, please send your comment to one of the following services: http://portal.etsi.org/chaircor/ETSI_support.asp Copyright Notification No part may be reproduced except as authorized by written permission. -
VPN 3000 Series Concentrator Reference Volume II: Administration and Monitoring Release 3.6 August 2002
VPN 3000 Series Concentrator Reference Volume II: Administration and Monitoring Release 3.6 August 2002 Corporate Headquarters Cisco Systems, Inc. 170 West Tasman Drive San Jose, CA 95134-1706 USA http://www.cisco.com Tel: 408 526-4000 800 553-NETS (6387) Fax: 408 526-4100 Customer Order Number: DOC-7814742= Text Part Number: 78-14742-01 THE SPECIFICATIONS AND INFORMATION REGARDING THE PRODUCTS IN THIS MANUAL ARE SUBJECT TO CHANGE WITHOUT NOTICE. ALL STATEMENTS, INFORMATION, AND RECOMMENDATIONS IN THIS MANUAL ARE BELIEVED TO BE ACCURATE BUT ARE PRESENTED WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED. USERS MUST TAKE FULL RESPONSIBILITY FOR THEIR APPLICATION OF ANY PRODUCTS. THE SOFTWARE LICENSE AND LIMITED WARRANTY FOR THE ACCOMPANYING PRODUCT ARE SET FORTH IN THE INFORMATION PACKET THAT SHIPPED WITH THE PRODUCT AND ARE INCORPORATED HEREIN BY THIS REFERENCE. IF YOU ARE UNABLE TO LOCATE THE SOFTWARE LICENSE OR LIMITED WARRANTY, CONTACT YOUR CISCO REPRESENTATIVE FOR A COPY. The Cisco implementation of TCP header compression is an adaptation of a program developed by the University of California, Berkeley (UCB) as part of UCB’s public domain version of the UNIX operating system. All rights reserved. Copyright © 1981, Regents of the University of California. NOTWITHSTANDING ANY OTHER WARRANTY HEREIN, ALL DOCUMENT FILES AND SOFTWARE OF THESE SUPPLIERS ARE PROVIDED “AS IS” WITH ALL FAULTS. CISCO AND THE ABOVE-NAMED SUPPLIERS DISCLAIM ALL WARRANTIES, EXPRESSED OR IMPLIED, INCLUDING, WITHOUT LIMITATION, THOSE OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT OR ARISING FROM A COURSE OF DEALING, USAGE, OR TRADE PRACTICE. IN NO EVENT SHALL CISCO OR ITS SUPPLIERS BE LIABLE FOR ANY INDIRECT, SPECIAL, CONSEQUENTIAL, OR INCIDENTAL DAMAGES, INCLUDING, WITHOUT LIMITATION, LOST PROFITS OR LOSS OR DAMAGE TO DATA ARISING OUT OF THE USE OR INABILITY TO USE THIS MANUAL, EVEN IF CISCO OR ITS SUPPLIERS HAVE BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES. -
Elementary Cryptanalysis Classification of Cryptanalytic Attacks
12 Elementary Cryptography Elementary Cryptanalysis The most direct attack on a cryptosystem is an exhaustive key search attack. The key size therefore provides a lower bound on the security of a cryptosystem. As an example we compare the key sizes of several of the cryptosystems we have introduced so far. We assume that the alphabet for each is the 26 character alphabet. Substitution ciphers: Simple substitution ciphers: 26! Affine substitution ciphers: ϕ(26) · 26 = 12 · 26 = 312 Translation substitution ciphers: 26 Transposition ciphers: Transposition ciphers (of block length m): m! Enigma : Rotor choices (3 of 5): 60 Rotor positions: 263 = 17576 Plugboard settings: 105578918576 Total combinations: 111339304373506560 The size of the keyspace is a naive measure, but provides an upper bound on the security of a cryptosystem. This measure ignores any structure, like character frequencies, which might remain intact following encryption. Classification of Cryptanalytic Attacks We do not consider enumeration of all keys a valid cryptanalytic attack, since no well- designed cryptosystem is susceptible to such an approach. The types of legitimate attacks which we consider can be classified in three categories. 1. Ciphertext-only Attack. 2. Known Plaintext Attack. 3. Chosen Plainext Attack. Ciphertext-only Attack. The cryptanalyst intercepts one or more messages all encoded with the same encryption algorithm. Goal: Recover the original plaintext or plaintexts, to discover the deciphering key or find an algorithm for deciphering subsequent messages enciphered with the same key. Known Plaintext Attack. The cryptanalyst has access to not only the ciphertext, but also the plaintext for one or more of the messages. Goal: Recover the deciphering key or find an algorithm for deciphering subsequent mes- sages (or the remaining plaintext) enciphered which use the same key. -
Bash Scripts for Avpres Verify Manifest(1)
verify_manifest(1) Bash Scripts for AVpres verify_manifest(1) NAME verify_manifest - Verify a checksum manifest of a folder or file SYNOPSIS verify_manifest -i input_path [-m manifest_file] verify_manifest -h | -x DESCRIPTION Bash AVpres is a collection of Bash scripts for audio-visual preservation. One of these small programs is verify_manifest.Itcreates a checksum manifest of a folder or file. Bash version 3.2 is required, but we strongly advise to use the current version 5.1. OPTIONS BASIC OPTIONS -i input_path,--input=input_path path to an input folder or file -m manifest_file,--manifest=manifest_file path to the manifest file If this parameter is not passed, then the script uses for a folder: <input_path>_<algorithm>.txt and for a file: <input_path>_<extension>_<algorithm>.txt ADVA NCED OPTIONS The arguments of the advanced options can be overwritten by the user.Please remember that anystring containing spaces must be quoted, or its spaces must be escaped. --algorithm=(xxh32|xxh64|xxh128|md5|sha1|sha256|sha512|crc32) We advise to use a faster non-cryptographic hash functions, because we consider that, for archival purposes, there is no necessity to apply a more complexunkeyed cryptographic hash function. The algorithm name can be passed in upper or lower case letters. The default algorithm is xxHash 128: --algorithm=xxh128 Note that until end of 2020 the default algorithm was MD5, which has the same checksum size than the xxHash 128 algorithm. Therefore, if you verity files with an MD5 checksum, then you may pass the option --algorithm=md5 in order to speed-up the verification. Also xxHash 32 and CRC-32 have the same checksum size. -
Guidelines on Cryptographic Algorithms Usage and Key Management
EPC342-08 Version 7.0 4 November 2017 [X] Public – [ ] Internal Use – [ ] Confidential – [ ] Strictest Confidence Distribution: Publicly available GUIDELINES ON CRYPTOGRAPHIC ALGORITHMS USAGE AND KEY MANAGEMENT Abstract This document defines guidelines on cryptographic algorithms usage and key management. Document Reference EPC342-08 Issue Version 7.0 Date of Issue 22 November 2017 Reason for Issue Maintenance of document Produced by EPC Authorised by EPC Document History This document was first produced by ECBS as TR 406, with its latest ECBS version published in September 2005. The document has been handed over to the EPC which is responsible for its yearly maintenance. DISCLAIMER: Whilst the European Payments Council (EPC) has used its best endeavours to make sure that all the information, data, documentation (including references) and other material in the present document are accurate and complete, it does not accept liability for any errors or omissions. EPC will not be liable for any claims or losses of any nature arising directly or indirectly from use of the information, data, documentation or other material in the present document. Conseil Européen des Paiements AISBL– Cours Saint-Michel 30A – B 1040 Brussels Tel: +32 2 733 35 33 – Fax: +32 2 736 49 88 Enterprise N° 0873.268.927 – www.epc-cep.eu – [email protected] © 2016 Copyright European Payments Council (EPC) AISBL: Reproduction for non-commercial purposes is authorised, with acknowledgement of the source Table of Content MANAGEMENT SUMMARY ............................................................. 5 1 INTRODUCTION .................................................................... 7 1.1 Scope of the document ...................................................... 7 1.2 Document structure .......................................................... 7 1.3 Recommendations ............................................................ 8 1.4 Implementation best practices ......................................... -
Download Instructions—Portal
Download instructions These instructions are recommended to download big files. How to download and verify files from downloads.gvsig.org • H ow to download files • G NU/Linux Systems • MacO S X Systems • Windows Systems • H ow to validate the downloaded files How to download files The files distributed on this site can be downloaded using different access protocols, the ones currently available are FTP, HTTP and RSYNC. The base URL of the site for the different protocols is: • ftp://gvsig.org/ • http://downloads.gvsig.org/ • r sync://gvsig.org/downloads/ To download files using the first two protocols is recommended to use client programs able to resume partial downloads, as it is usual to have transfer interruptions when downloading big files like DVD images. There are multiple free (and multi platform) programs to download files using different protocols (in our case we are interested in FTP and HTTP), from them we can highlight curl (http://curl.haxx.se/) and wget (http://www.gnu.org/software/wget/) from the command line ones and Free Download Manager from the GUI ones (this one is only for Windows systems). The curl program is included in MacOS X and is available for almost all GNU/Linux distributions. It can be downloaded in source code or in binary form for different operating systems from the project web site. The wget program is also included in almost all GNU/Linux distributions and its source code or binaries of the program for different systems can be downloaded from this page. Next we will explain how to download files from the most usual operating systems using the programs referenced earlier: • G NU/Linux Systems • MacO S X Systems • Windows Systems The use of rsync (available from the URL http://samba.org/rsync/) it is left as an exercise for the reader, we will only said that it is advised to use the --partial option to avoid problems when there transfers are interrupted. -
Configuring SSH and Telnet
Configuring SSH and Telnet This chapter describes how to configure Secure Shell Protocol (SSH) and Telnet on Cisco NX-OS devices. This chapter includes the following sections: • About SSH and Telnet, on page 1 • Licensing Requirements for SSH and Telnet, on page 3 • Prerequisites for SSH and Telnet, on page 3 • Guidelines and Limitations for SSH and Telnet, on page 3 • Default Settings for SSH and Telnet, on page 4 • Configuring SSH , on page 4 • Configuring Telnet, on page 15 • Verifying the SSH and Telnet Configuration, on page 17 • Configuration Example for SSH, on page 18 • Configuration Example for SSH Passwordless File Copy, on page 19 • Additional References for SSH and Telnet, on page 21 About SSH and Telnet This section includes information about SSH and Telnet. SSH Server You can use the SSH server to enable an SSH client to make a secure, encrypted connection to a Cisco NX-OS device. SSH uses strong encryption for authentication. The SSH server in the Cisco NX-OS software can interoperate with publicly and commercially available SSH clients. The user authentication mechanisms supported for SSH are RADIUS, TACACS+, LDAP, and the use of locally stored usernames and passwords. SSH Client The SSH client feature is an application that runs over the SSH protocol to provide device authentication and encryption. The SSH client enables a Cisco NX-OS device to make a secure, encrypted connection to another Cisco NX-OS device or to any other device that runs the SSH server. This connection provides an outbound Configuring SSH and Telnet 1 Configuring SSH and Telnet SSH Server Keys connection that is encrypted. -
New Comparative Study Between DES, 3DES and AES Within Nine Factors
JOURNAL OF COMPUTING, VOLUME 2, ISSUE 3, MARCH 2010, ISSN 2151-9617 152 HTTPS://SITES.GOOGLE.COM/SITE/JOURNALOFCOMPUTING/ New Comparative Study Between DES, 3DES and AES within Nine Factors Hamdan.O.Alanazi, B.B.Zaidan, A.A.Zaidan, Hamid A.Jalab, M.Shabbir and Y. Al-Nabhani ABSTRACT---With the rapid development of various multimedia technologies, more and more multimedia data are generated and transmitted in the medical, also the internet allows for wide distribution of digital media data. It becomes much easier to edit, modify and duplicate digital information .Besides that, digital documents are also easy to copy and distribute, therefore it will be faced by many threats. It is a big security and privacy issue, it become necessary to find appropriate protection because of the significance, accuracy and sensitivity of the information. , which may include some sensitive information which should not be accessed by or can only be partially exposed to the general users. Therefore, security and privacy has become an important. Another problem with digital document and video is that undetectable modifications can be made with very simple and widely available equipment, which put the digital material for evidential purposes under question. Cryptography considers one of the techniques which used to protect the important information. In this paper a three algorithm of multimedia encryption schemes have been proposed in the literature and description. The New Comparative Study between DES, 3DES and AES within Nine Factors achieving an efficiency, flexibility and security, which is a challenge of researchers. Index Terms—Data Encryption Standared, Triple Data Encryption Standared, Advance Encryption Standared.